Mockup shadow is grainy on version CC 2017.0.1 but not on CC 2015.5.0

I downloaded a free glass jar mockup and no matter what I do, the smart object shadow layer consistently results in this grainy texture. No other mockups have issues, and a friend editing the same file in version CC 2015.5.0 did not have this issue. I have tried changing the cache levels and making a new shadow, but nothing changes. None of the smart object or layers have a blending mode on them as well.